It’s not a good time to be a flying fox. Justin Welbergen, from the University of Cambridge, has just published some new research on them and he thinks climate change means they are all going to die.

The issue for the animals, which are not foxes at all but fruit bats, is that they’re just not that good with heat. This is a bit of a problem if you live in an Australia that is getting slowly hotter. Welbergen and his colleagues found that temperature extremes caused mass die-offs, with females and the young being especially vulnerable. When temperatures reached 42.9°C, thousands of the bats keeled over and flapped no more (paper should appear here today).

Climate change may also be benefiting some types of the bat, by allowing them to expand their range by reducing the number of cold nights, which they can’t tolerate. “If so, this provides an example of how climate change may act like a double-edged sword,” write Welbergen and co, “it can cause a species to expand its distribution in response to a reduction in the number of cold nights, while putting the same species at an increased risk from extreme warm events.

It has been acknowledged before that climate change is causing changes in species distributions. Nature Reports Climate Change had an article on this recently, noting that in Australia some possums have been getting so hot they fell out of their trees.

Stefan Klose, one of the research team, told the Daily Telegraph, “In a very dramatic way we see the outcome of extreme climate events that are predicted to increase as a result of climate change by the Intergovermental Panel on Climate Change. These animals are simply not able to cope with higher temperatures and so they die. They are the seed dispersers for Australia’s rainforest so the ecosystem effects could be very considerable.”

According to the Times over 30,000 fruit bats have died since 1994 in heat waves “associated with global warming”. Conservation Magazine thinks monitoring roosts when high temperatures are expected is the way forward. This isn’t going to please fruit growers. According to the North Queensland Register a “‘plague” of flying foxes is tormenting the regions’ farmers. A small piece of good news for the animals: lychee farms in North Queensland have been told to dismantle electric grids used to stop bats eating the tasty fruit (ABC).

Image: courtesy of Justin Welbergen

Cross-posted from Daniel Cressey on The Great Beyond.